Electronic Ink Display Test 1
12 Mar 2016Here’s the idea – a fun weekend project
I wanted to fool around with hardware for displays a little bit. A couple people made some projects with eink that looked really neat. See essentialscrap and spritesmods for those inspiring projects. They both use microcontrollers instead of FPGAs to drive their eink displays and it looked like the firmware for it wasn’t too complex. The SpritesMods one even had some oscilloscope images to go by.
So I thought I’d put together a fun KiCAD layout and write some firmware. Not a huge deal as I put together schematics for work sometimes and work closely with the layout guy. Boards can be had for kinda cheap these days, a 4 layer board of 10cm x 10cm was really overkill (and only 50$!). Of course I made mistakes, but nothing I couldn’t fix. They say Eagle is great because you get huge libraries of packages but I tend to comb through that stuff and I was glad to not have errors on that part this time. I tend to work with Microchip people and I haven’t used their PIC32 in a while, so I thought I’d try that, too. Add some RAM memory in case I could try some kind of animating and a microSD card slot to maybe store images and a LiPo battery charger and the +/- 20, 15 v stuff from a reference design for the display’s setup.
One of the reference projects connected his to the internet, but I was more interested in just bringing the thing to conferences or shows or meetups and showing off some project there.
It’s on github
I have the first iteration of the project here.
It looks like this right now:
Not working though
I’m having some trouble. It goes through one row nicely but then something is stuck and it displays that row continually. So for example, if I tried to make the top half of the display white and the bottom half black, then it would flash white briefly before going all dark. Been like this for a while now and I don’t get it based on what I’ve seen from the two example projects.
One says to drive CKV high for a short time to go to the next row, the other project says to pull it down to go on. I’m confused and frustrated at the mess. Maybe put more time into sorting it out later or see if anyone wants to help or explain.